Noon Barbari
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Estadística

Median

Middle value of a sorted series — robust to outliers, unlike the mean.

The median is the middle value of a sorted series — half the observations lie above it, half below. It is a robust measure of central tendency: a few extreme outliers move the median much less than they move the mean.

In trading the median trade size, median holding period, or median drawdown often tells you more than the mean about typical experience. The mean can be dominated by a handful of outliers; the median describes the day-to-day.

When the return distribution is symmetric, mean and median coincide. When it is skewed (as most financial return distributions are), mean and median diverge — by how much is itself a useful statistic.

Fórmula

median(x) = x_{(⌈N/2⌉)} if N is odd; (x_{(N/2)} + x_{(N/2+1)}) / 2 if N is even

Ejemplo

Trade returns sorted: [-3%, -1%, 0%, 2%, 50%]. Mean = 9.6%, median = 0%. The median is a much better description of what most trades did.

Cómo Noon Barbari usa Median

Cada concepto aquí está implementado en la plataforma. Abre la documentación o la herramienta correspondiente para verlo en acción.

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